Peening hammer having removable striking head



Dec. 13, 1949 ANDERSON 2,491,295

PEENING HAMMER HAVING REMOVABLE STRIKING HEAD Filed Nov. 5. 1945INVENTOR.

Patented Dec. 13, 1949 UNITED" STATES PATENT OFFICE This inventionrelates to improvements in a peen for a hammer head and has specialreference to a device applicable to a hand hammer; used in the art ofrepairing automobile renders or the likelin' restoring the normalappea'rance' or the surface of a previously dented, bent or otherwisedamaged fender, or body of an automobile.

It is well known that whensuch force is applied either hymns orotherwise to deranged th n. me a s e s. c -.a$..au bi n c it becomesvery hard to bring the surface of the metal back to normalcy withoutleaving an impression thereupon of the face of the tool employed. V

In other words, it is very'ha'rd in many 1nstance's' to judge correctlythec'ontour of the surface being engaged by the face'of the hammer toavoid such defacement; and to overcome this problem is the principalobject of the present invention.

Another object is to so shape the co-operative parts of the peen of sucha hammer that they will most readily function to hold the jointed partsthereof in close ideal working position at all times as well as morereadily assume normal axial relation of the face of the peen to the headof the hammer.

Other objects and advantages will appear during the further descriptionof the embodiment here illustrated.

Referring now to the accompanying drawing forming part of thisapplication:

Fig. 1 is a side elevational view of one type of hand hammer head withone of the improved peens shown in vertical section upon one terminus ofsaid head, and

Fig. 2 is a transverse sectional view on the line 2-2 Fig. 1.

In the drawing, l represents the head of the hammer comprising the twoopposed axially aligned shank-like portions 2 and 3.

The shank 3 adjacent its extreme end is preferably reduced in diametersomewhat as at 4 and the extreme end is enlarged and of semisphericalshape as at 5 with its greatest diametrical dimension somewhat more thanthat of the reduced adjacent shank portion 4 to provide the flat steppedledge or annulus 5 as a seat for the smaller end of the conicalexpansive spring I.

Now the peen proper comprises the cylindrical hollow body portion 8 withthe spring chamber 9 therein and the circular head portion l [lpreferably somewhat larger in diameter than the body portion andterminating in the slightly convexed 2- face II. The head It has formedtherein a central semi-spherical seat for rockable reception of thesemispherical terminus 5 of the hammer head. This seat is' of somewhat lessdepth than the't'erminus 5 in order to insure a free stepped seat'abdutthe shank portion 4 for the spring l than the terminal member 5 so as toallow free passage th'erethroligh of the latter, thus there is formedthe'circu'lai' ied elsebove the entrance to the chamber and thereinfor'suitable impingement for the larger extremity of the spring 1 in itsconstant action of keeping the een in ideal working contact with theshank of the hammer head.

The spring I is of a size and strength to be readilyslipped over theenlarged terminus 5 of the hammer head shank, then contractedsufficiently and tucked into the chamber 9 through the entrance I 2until it readily assumes its proper functioning position as shown.

As convenience in removal of the spring I when occasion arises for such,there is provided the cut or slot I3 which extends diametrically acrossthe open end of the peen and through the spring ledge I5 most clearlyseen in Fig. 2 of the drawing and through either extremity of which thelargest upper coil of the spring is accessible as by a small pointedinstrument such as a small file shank or the like for compressing thespring and working it upwardly out of the chamber 9 simultaneously withthe terminal 5 of the hammer shank.

The inner end M of each terminal portion of the slot I3 is slightlyflared to obviate the possibility of same being restricted by repeatedengagement with the shank portion 4 during the hammering processmaterial in actual practice.

From the foregoing it is apparent that the paramount feature is that ofkeeping the workengaging portion of the peen in constant frictional, butyieldable rockable engagement with the shank portion of the hammer headduring the hammering process and which provision has proved material inactual practice.

Another notable feature in this type of peen when in actual use is thefact that at every retraction of the hammer head from a blow which hadmade the peen function at all out of its normal axial alignment, itwould immediately reassume such a normal alignment for a subsequentblow. which obviously is essential to the success of the tool.

Applicant has determined that the spring being of conical shape has amuch greater tendency to maintain the peen in its proper normal axialalinement with the hammer shank, than a plain coil spring.

What I claim is:

1. A new article of manufacture: a hammer head including a cylindricalshank portion, a portion of said shank adjacent one end thereof being ofreduced diameter, the end surface of said end of the shank beingsemi-spherical and of a diameter greater than said portion of reduceddiameter to provide an annular spring seat at the juncture of saidsemi-spherical portion with said portion of reduced diameter, a hollowone piece peen on said end portion and having a substantiallysemi-spherical recess formed in the inside surface of one end of saidpeen to rockably receive said semi-spherical end of the shank, theoutside surface of said end of the peen forming a slightly curvedpeening surface, the opposite end of said peen having an opening formingan entrance portion to the chamber of said peen, said opening beingsubstantially in axial alinement with said recess and of reduced size tothe transverse dimension of said chamber but of a size to freely admitthe end of said shank whereby a spring engaging seat is provided aboutsaid entrance, a conical expansive spring within said chamber and aboutsaid shank and with its smaller terminus impinging said spring seat onsaid shank and the opposite terminus impinging said spring seat on thepeen to bias said peen and hammer head towards each other, and adiametrically disposed slot through the open end of said peen forconvenience in removing said spring.

2. A hammer head including a cylindrical shank portion formed integraltherewith, a portion of said shank adjacent one end thereof being ofreduced diameter, the end surface of said end of the shank beingsemi-spherical and of greater diameter than said portion of reduceddiameter providing an annular spring seat at the juncture of saidsemi-spherical portion with said portion of reduced diameter, aone-piece hollow peen on said end portion and having a semi-sphericallyshaped recess formed in the inside surface of one end of said peen torockably receive said semispherical end of the shank, the opposite endof said peen having an opening forming an entrance to the chamber ofsaid peen, said opening being substantially in alinement with saidrecess and of reduced size to the transverse dimension of said chamberbut of a size to freely admit the end of said shank so that a springseat is formed about said entrance, a conical expansive spring aboutsaid shank within said peen and having its smaller end engaging saidspring seat on said shank and its larger end engaging said spring seatabout said entrance on said peen to bias said peen and shank inengagement and normally in axial alinement, and a transverse diametricalslot through said opposite end of said peen for more convenient accessto said spring to remove same from Within said hollow peen whenrequired.

NORMAN ANDERSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 217,546 Murdock July 15, 18791,104,564 Snyder July 21, 1914 1,284,446 Potts Nov. 12, 1918 2,198,764Edwards Apr. 30, 1940

